Load lock

ABSTRACT

The load lock of the present invention is to lock the beam of a pallet rack structure to an upright of an end frame and includes an L-shaped bolt having a shank slidably extending through aligned holes in the upright and an end plate of the beam and having a headed handle portion extending through a contoured slot in the beam wall adjacent the end of the beam. The handle portion is encircled by a generally cylindrical spring metal retainer having a pair of extensions embracing the bolt between the shank and the handle portion, having diametrically opposed projecting tabs engaging the inner face of the beam wall adjacent the slot and with cooperation of the head to prevent removal of the load lock, and having projections engageable with the edges of the contoured slot to hold the load lock in any adjusted position of the shank with respect to the hole through which it extends in the beam end plate. The load lock is so constructed than when properly inserted in a contoured slot with its shank projecting into the beam end plate opening it cannot be removed. A modified form of beam slot is made long enough to permit removal of the shank from the beam end plate hole and the removal of the load lock from the slot; a load lock movement limiting device is provided to prevent this from being done unintentionally.

United States Patent [1 1 McConnell et al.

June 26,- 1973 1 LOAD LOCK [75] Inventors: Kennedy McConnell, Riverdale;

Raymond F. Juechter, Glenwood, both of 111.

[52] U.S. Cl. 211/177, 287/l89.36 R [51] Int. Cl A471 5/10, Fl6b 17/00[58] Field of Search 211/177, 176, 182,

211/183; 287/54 C, 189.36 R, 389.36 C, 189.35; 292/147, 152; l5l/41.75,69; 85/8.8; 52/720, 721

[56] References Cited UNITED STATES PATENTS 2,246,457 6/1941 Schultz85/1 H UX 2,280,084 4/1942 292/152 3,070,237 12/1962 Fullerton et al.211/176 3,164,054 l/l965 Biesecker 85/8.8 3,351,212 11/1967 McConnell211/177 FOREIGN PATENTS OR APPLICATIONS 917,384 9/1946 France 151/4l.75810,117 8/1951 Germany 292/147 938,492 10/1963 Great Britain...l51/41.75 240,745 292/152 4/ 1946 Switzerland Primary Examiner-Ramon S.Britts Attorney-Curtis F. Prangley, David A. Vogel and J. Terry Stratmanet a1.

[5 7] ABSTRACT The load lock of the present invention is to lock thebeam of a pallet rack structure to an upright of an end frame andincludes an L-shaped bolt having a shank slidably extending throughaligned holes in the upright and an end plate of the beam and having aheaded handle portion extending through a contoured slot in the beamwall adjacent the end of the beam. The handle portion is encircled by agenerally cylindrical spring metal retainer having a pair of extensionsembracing the bolt between the shank and the handle portion, havingdiametrically opposed projecting tabs engaging the inner face of thebeam wall adjacent the slot and with'cooperation of the head to preventremoval of the load lock, and having projections engageable with theedges of the contoured slot to hold the load lock in any adjustedposition of the shank with respect to the hole through which it extendsin the beam end plate. The load lock is so constructed than whenproperly inserted in a contoured slot with its shank projecting into thebeam end plate opening it cannot be removed. A modified form of beamslot is made long enough to permit removal of the shank from the beamend plate hole and the removal of the load lock from the slot; a loadlock movement limiting device is provided to prevent this from beingdone unintentionally.

27 Claims, 12 Drawing Figures aoaaaaaoa c ob Que PATENTED JUII26 I975SHEEI10F3 FIG.!

DD 000 0000 a QQQ QQ INVENTORS KENNEDY MCCONNELL RAYMOND E JUE CH TE RTTYS.

PAIENImJms ms 3. 741; 405

sum: or 3 FIG. I2

LOAD LOCK The present invention relates to load locks for use in lockingthe beams to the vertical frames of pallet racks. A typical pallet rackis disclosed in George E. Rasmussen U.S. Pat. No. 3,042,221 dated July3, 1962. As disclosed in this patent, a pallet rack comprises at least apair of end frames having vertical uprights connected together byhorizontal and diagonal cross bracing. The end frames are interconnectedby beams which have lug and slanted key slot connections with theuprights. Locking of the beam to the upright is provided by a slidingbolt which has a shank extending through aligned holes in the uprightbeam end plate and a Z- shaped bracket welded to the inner face of theend plate. The bolt is L-shaped and has a handle projecting through anL-shaped slot in a wall of the beam adjacent the end plate. Thearrangement is such that the bolt cannot be removed from the alignedholes in the end plate and bracket and the L-shaped slot in the beam.

The load lock of the present invention contemplates use of a lockingbolt which is assembled to the beam after the beam end plate has beenwelded in place. In using the load lock of the present invention, theload lock is mounted after the beam has been completed, and the size andlength of the beam has no affect on mounting the load lock thereto.

The load lock is an L-shaped bolt having a locking shank and a handle.The handle has a head and is fitted with a spring metal retainertherebelow which keeps the bolt secured to the beam and retainedvertically and also holds it in an adjusted position in a contoured slotin the beam so that the shank is either in load locking or unlockedpositions.

It is therefore a principal object of the present invention to provide anew and improved load lock for use in pallet rack beams which lock ispositive in its opera tion, is easily installed in a completed rackbeam, and cannot be unintentionally or accidentally removed.

Another object is to provide a new and improved load lock having a novelspring metal retainer around the handle portion of the lock to preventits removal from the rack beam and to hold it in an adjusted position ina contoured slot in the beam wall.

Yet another object is to provide a new and improved load lock which ismounted on the front of the beam so that the user can visually confirmthe position of the load lock.

Other objects and advantages will become apparent from the followingdescription taken in conjunction with the accompanying drawings andappended claims.

FIG. 1 is a perspective view of a pallet rack structure utilizing theload lock of the present invention;

FIG. 2 is an elevational view, partially broken away, showing a beammounted on a frame upright and one load lock in locking position andanother in withdrawn position;

FIG. 6 is an elevational view on the scale of FIG. 5 and taken from theleft side thereof showing the handle and the retainer in the beam wallslot;

FIG. 7 is a sectional view on an enlarged scale taken along the line 7-7of FIG. 5, looking in the direction of the arrows;

FIG. 8 is a sectional view taken along the line 88 of FIG. 5, looking inthe direction of the arrows;

FIG. 9 is a fragmentary elevational view, partially broken into sectionshowing a modified form of slot from which the load lock may be removed;

FIG. 10 is an enlarged transverse sectional view of device for limitingthe load lock movement in the slot and is taken along the line 10-10 ofFIG. 9 looking in the direction of the arrows;

FIG. 11 is a view similar to FIG. 9 showing the movement limiting deviceremoved; and

FIG. 12 is a view similar to FIG. 10 showing the load lock in withdrawnand in turned positions prior to removal from the slot.

FIG. 1 of the drawings illustrates a pallet rack 20 having end frames22, each of which is formed of a pair of uprights 24 interconnected byhorizontal braces 26 and diagonal braces 28, the braces being welded tothe uprights 24.

The frames 22 are interconnected by pallet supporting tubular beams 30,which may be made of a pair of channel shapedbars welded together. Eachbeam 30 has angle shaped end plates 32 welded to the opposite open endsthereof. Flange 34 of the angle 32 is fitted with a pair of headed lugs36 which engage in slanted key hole shaped slots 38 in the upright 24 bymeans of which the end of the beam 30 is removably secured to therespctive upright 24. The arrangement is such that the angled end plate32 contacts the frame upright 24 along two faces to provide initialassurance that the beam 30 will not twist or rotate relative to theframe 22 and that when pallets are supported on the rack 20 by bridgingacross between the beams 30, the pallets and the loads carried therebywill be safely stored.

As seen in FIGS. 1, 2, and 3, the beam 30 has an outer wall 40 whichforms the base of one of the channels of which the beam is made.Adjacent each beam end a contoured slot 42 is formed in the front wall,the slot shape being most clearly shown in FIG. 7. The slot 42 receivesand limits the movement of a load lock 44.

The load lock 44 base is an L-shaped bolt 46 which carries a retainer 48made of spring metal on that portion thereof which projects through thecontoured slot 42.

The bolt 46 has a shank 50 which slidably projects through a hole 52 inthe end plate 32 and an aligned hole 54 in the vertical upright 24. Whenthe shank 50 is in the full line position, shown in FIGS. 2 and 3 andextends through both of the holes 52 and 54, it is not possible to movethe beam 30 with respect to the upright 24 in a direction as todisengage the lugs 36 from the key hole slots 38 nor to twist or rotatethe beam relative to the upright. The load lock 44 in locking positiontherefore insures that the beam 30 remains fixed to the upright and thatthe load carried on the beam is properly transmitted to the frame member22.

The bolt 46 has a head 56 at the outer end of a handle portion 58 of thebolt 46 and load lock 44 and has its underside slidable along the outerface of the beam wall 40 adjacent the contoured slot 42. The retainer 48encircles or encloses the greater part of the handle por- I I tion58 bya generally cylindrical body 60, FIG. 7. As seen alsoin FIG. 6, thecylindrical body 60 is formed of a generally rectangular piece of metalshaped into cylindrical form and having an opening 61 adjacent to lockthe cylindrical body 60 about the'handle portion It is essential thatthe retainer 48 b e mounted on the bolt 46 in a position that resistsappreciable turning it remains secured in place and cannot beunintentionally or accidentally lost from the beam 30.

As seen by acomparisonof the two different posi- .tions of theload lock44 inFlG. 2and the solidand dot dash line positions in FIG. 3,'thej loadlock 44is intended to be movedlengthwise of the contoured slot 42 and tobe retained inthe positions selected bythe asthereof on the handleportion 58. To effectthis result the body 60 of the retainer is formedwith apair of diametrically opposed extensions 64 which embracebend 66in thebolt 46 between the shank 50and thehanclle portion 58. As seen inFIG. 4 the bolt 46 initiallyis.

straight and the retainer is slipped thereover so that its side of thehead 56. The bolt is bentto form the right angle bend 66 so that thehandle portion 58 is normal to the shank 50 as'seen by comparing thefull line and;

dot-dash line shapes of FIG. 4. During this time the extensions 64 liealongthe outside of the bend 66 and effectively prevent rotation of theretainer 48 after the The retainer 48 is also restrained againstlongitudinal bend has been made. I

movement with respect to the handle portion 58,such restraint beingprovided at one end by the head 56 and at the other end by a projection57 formed during the right angle bending of the bolt 46 from thestraight condition thereof to the right angle condition thereof as Hlustrated in FIG. 4. The projection 57 cooperates with the head 56positively to position the retainer 48 onthe handle portion 58 duringall uses of the load lock 44.

The retainer 48 has the dual function of assisting in holding the loadlock 44 in the contoured slot 42 in the beam wall and also in adjustedlongitudinal position of the shank 50. For the first function the body60 of the retainer is formed with two pairs of diametrically opposedtriangular tabs 68 which are struck. out during the forming process andprior to mounting the retainer ing toward the center of the slot bytheinwardly pro-f jecting edge arcs 80. As a matterof fact, FIG. 7 showsthat the general cylindricalretainer 48 and the partly j circular edge78have a-co mmon centerwhich permits sembler of the pallet rack(20."Referring primarily to FIGS. 2, Sand7, the retainer48 is shown to beformed with a pair of diamet'rically'opposed projections 76. l

which engagethe edges of the slot 42 adjacent the tab faces 70 andimmediatelybelow the head S6to hold the M load lock 44 intheselectedposition.

. The slot42 as seen most clearly in FlGfTincludesa pair of generally;cylindrical ends 7 8 surrounde d by iri wardly facingrounded arcs180 andan interconnecting" j straightedge 82;At its extreme positionsthe loadlock end opposite the extensions 64 rests against the under- 44 isengagedin one or the other of the cylindrical ends 78. In thesepositions, one of which is shown in FIG. 7, the projections 76 on theretainer 48 engage the cyline drical edge 78 and are normally preventedfrom movthe projections 7mm the retainer body 60 to be at max imumexpansion'whichisthe norml positiomShould it be desiredto move the loadlock 44 to the opposite end of the slot 70, the head is graspedand slidalong the surface of the outer wall 40. This movement engages theretainer projections76 on the retainer 48 with the f slot edgearcs-80jandcompresses the projections76by the resiliency of thespringrnetal of which theretainer 1 j y is made. Thislmovement is permitted bya compression of the projections 76. The projections 76 next appear Iopposite the straight edges 82 but these edges are suffi- 'cientlycloseto eachother that the tab faces'70 prevent 48 on the load lock. Thetabs 68 have edges or faces70 V venting any significant longitudinal andvertical movement of the handle portion 58 within the slot 42.

withdrawal of the bolt 46,. andthe sliding movement if continued untilthe projections 76 contact and are compressed by the other setofinward'arcsor projec tions 80 at which time the unit passes into theother partly circular portion 78 of the slot42. If FIGS. 3 and 7 becorrelated to illustrate the foregoing, the'full line The tabs 68 areformed with converging edges 72 which extend from the tips of the faces70 to a point in the body 60. The purpose of these edges is to permittemporary collapse of the tabs 68 during the insertion of the load lock44 through the slot 42. The loadlock and its tapered end 74 fed throughthe hole 52 inthe end plate 32. This will bring the tips of theconverging edges 72 against the edges of the slot 42. In thisposi tionthe bolt is driven'inwardly either by striking its beam. In thisembodiment of the invention the faces 70 prevent extricatingthe loadlock 44 from the slot 42 in the manner in which it was inserted, andconsequently I 44 should be inserted into the beam 30 prior to mountingthe beam on the end frame uprights 24. The shank 50 of the bolt isinserted through the contoured slot 42 cured in the contoured slot42between the tab faces and the underside-of thehead 56. Rotation of theload lock 44 about the handle portion 58 is prevented be cause at allpositions of the load lock 44 at least the tip 74 of the shank lies inthe opening 52 in the. beam end plate 32. -In locking position theshank50 projects through the alignedholes '52 and 54 in thebeam endplate 32 and the upright'24. It is impossible for reasons which havepreviously been set forth in detail tore-' move this load lock fromthecontoured slot 42, and the V assembly remains intact. It further will beappreciated thereof, thereby facilitatingready inspectioni'and conthatthe load lock 44 is disposed on the outwardly disposed or front wall 40of each of the beams 30, and as j a consequence, a user can visuallyascertain whether theload lock 44 is in the locked or unlocked positionfirmation that the load lock 44 is in the desired position thereof.

A modified form of assembly is shown in FIGS. 9 through 12. In this formthe load lock 44 is constructed in precisely the same manner as wasdescribed with respect to FIGS. 1 through 8 and is inserted in themanner previously described. It may, however, be removed without damage.

In the modified assembly a contoured slot 42A is provided in the beam30, and its left end (closest to the beam plate 32) is precisely thesame as the slot 42 shown in FIG. 7. The right or remote end, however,has a semicircular portion 84 interconnected with a short straightportion 86 and joining a pair of inward projections or arcs 88 like theprojections 80 and having the same functions. In FIGS. 9 and 11 thedot-dash line at the right end of the slot 42A shows the normaldesirable limitations on the movement of the handle 58 of the load lock44, but under certain circumstances where it may be desired to removethe load lock 44 from the beam 40, due perhaps to prior damage to theshank 50, the shank should be removed completely from the hole 52in thebeam end plate 32. Under these conditions the load lock 44 would bemoved to the full line position shown in FIG. 12 where it is seen thateven the tapered end 74 is clear of the beam end plate hole 52 and theload lock 44 may be turned within the cylindrical circular portion 84 ofthe slot 42A. The projections 76 do not function to inhibitsignificantly the passage of the retainer 48' past the inwardprojections 88 and they may be moved into the opposite straight sections82 of the slot. At this point the tab faces 70 will no longer engage theinner face of the beam wall 40 and the retainer 48 can be slipped fromthe slot 42A and the load lock 44 manipulated in such fashion as to beremoved from the contoured slot 42A.

Under normal use of the structure, however, this extreme movement of theload lock 44 is not desirable, and a motion limiting assembly, seen mostclearly in FIGS. 9 and 10, is provided. This assembly comprises a bolt92 extending through a hole 94 in the outer wall 40 inwardly of the endof the contoured slot 42A. The bolt 92 is provided with a washer 96which may be welded or brazed onto or formed integrally with bolt head98. The washer 96 is sufficiently large so that it overlies a portion ofthe inner end of the circular end 84 of the slot 42A and limits thenormal withdrawal movement of the load lock 44 to the same extent asthat permitted by the slot 42 illustrated in FIGS. 1 through 8.

The assembly is retained in place by a wing nut 100 threaded onto theshank of the bolt 92. When it is desired to remove the load lock 44 fromthe slot 42A the motion of the wing nut 100 is arrested by a fingerinserted through the slot 42A while unscrewing the bolt 92. This freesthe structure of the movement limiting device, FIGS. 11 and 12, and themovement of the load lock 44 is such that it goes to the extreme rightor inner end of the slot 42A and can be removed in the manner previouslydescribed.

A simpler version of this arrangement would be to weld or braze a nut tothe inner face of the beam wall 40 at the hole 94 so that the bolt 92could be screwed directly thereinto without having one manually hold thewing nut 100 in place. This would also prevent inadvertently droppingthe wing nut inside the beam as might happen in view of the relativelysmall space which is afforded by the maximum cross dimension of the slot42A.

From the foregoing description it is clear that the advantages andobjectives of the present invention which were set forth at the outsetof this specification have been attained by the structure described andshown.

What is claimed as new and desired to be secured by United StatesLetters Patent is:

l. A load lock for use in a pallet rack for locking a beam end to anupright in a frame, comprising in combination an L-shaped bolt and abeam, said bolt having a shank aligned with and slidable through a holein the end of the beam and adapted to slide through an aligned hole inthe frame upright, a handle portion integral with said shank at rightangles thereto and having an enlarged head on the free end thereof andextending through a contoured movement-limiting slot in a wall of thebeam, said head engaging an exterior surface of said beam adjacent tosaid slot, a retainer including a generally cylindrical body encirclingsaid handle portion to restrict the latter for sliding movement in saidslot, resilient means on said cylindrical body slidably engaging theedge surfaces of said slot to retain said bolt in an adjusted position,and means on said handle portion positively positioning and holding saidretainer on said handle portion between said head and said positioningmeans.

2. The combination set forth in claim 1', wherein said positioning meansis disposed adjacent to the juncture between said handle portion andsaid shank.

3. The combination set forth in claim 1, including means on saidcylindrical body embracing the bend in said bolt between said shank andsaid handle portion to resist turning movement of said body on saidhandle portion. 8

4. The combination set forth in claim 1, wherein said retainer includespairs of diametrically opposite tabs projecting outwardly from said bodyand engageable with the inner surface of the beam wall adjacent saidcontoured slot.

.5. The combination set forth in claim 4, wherein said tabs projectoutwardly from said body and face in spaced relationship the undersideof said handle portion head so as to accommodate therebetween the beamwall adjacent said contoured slot.

6. The combination set forth in claim 1, wherein said resilient meanscomprises a pair of diametrically opposite projections outstanding fromsaid body and engageable with the edge surfaces of said contoured slotto retain said bolt shank in longitudinally adjusted position.

7. The combination set forth in claim 6, wherein said contoured slotedge surfaces have a pair of partly circular ends interconnected by astraight section, and have inward projections at the termini of saidstraight section to retain said handle portion within the confines ofeither of said circular ends.

8. The combination set forth in claiml, wherein said retainer includespairs of diametrically opposite tabs projecting outwardly from said bodyand engageable with the inner surface of the beam wall adjacent saidcontoured slot, and said resilient means comprises a pair ofdiametrically opposite projections outstanding from said body betweensaid tabs and the underside of said head and engageable with the edgesurfaces of said contoured slot to retain said bolt shank inlongitudinally adjusted position.

9. The combination set forth in claim 1, wherein said contoured slotedge surfaces have a pair of partly circular ends, that end nearest thebeam end being bounded by a pair of inward projections, the other endbeing connected to a pair of straight surface portions spaced apart thediameter of said other end, said straight portions having their terminiremote from said other end connected to a second pair of inwardprojections, and straight sections interconnecting said pairs of inwardprojections, the distance between said partly circular ends being suchthat when said handle portion is in said other circular end said shankis withdrawn from the hole in the beam end and said bolt may be rotatedto remove said restricting means from engagement with the inner surfaceof the beam wall so that the load lock may be removed from the beam.

10. The combination set forth in claim 9, including removable means forlimiting movement of said handle portion into said other circular end soas to retain said shank in the hole in the beam end.

ll The combination set forth in claim 10, wherein said removable meanscomprises a stop member overlying a portion of said other circular-endand a bolt to hold said stop member in movement limiting position sothat said shank may not be slid from the'hole in the beam end. V

12. A beam for use in a supporting structure comprissaid body portion, ahandle portion integral with said shank at right angles thereto andhaving anenl arged head on the free end thereof and extending throughsaid contoured slot, said head engagingan exterior surface of said beamadjacent to saidslot, means on said handle portion to restrict thelatter for sliding movement in said contoured slot, and resilient meanson said handle portion slidably engaging the edge surfaces of 7 saidcontoured slot to retain said shank in an adjusted position in said endflange hole.

13. The combination set forth in claim 12, wherein said restrictingmeans and said resilient means are incorporated in one unit having agenerally cylindrical body encircling said handle portion.

14. The combination set forth in claim 13, including means on saidcylindrical body embracing the bend in said bolt between said shank andsaid handle portion to resist turning movement of said body on saidhandle 1 portion.

15. The combination set forth in claim 13, whereinsaid restricting meanscomprises pairs of diametrically opposite tabs projecting outwardly fromsaid body and engageable with the inner surface of said beam bodyportion wall adjacent said contoured slot.

16. The combination set forth in claim 15, wherein said tabs projectoutwardly from said body and face in spaced relationship the undersideof said handle portion head so as to accommodate therebetween said beamwall adjacent said contoured slot.

17. The combination set forth in claim 13, wherein said resilient meanscomprise a pair of diametrically opposite projections outstanding fromsaid body and engageable with said edge surfaces of said contoured slotto retain said bolt shank in longitudinally adjusted position withinsaid end flange hole 18. The combination set forth in claim 17, whereinsaid contoured slot edge surfaces have a pair of partly circular endsinterconnected by a straingt section, and have inward projections at thetermini of said straight section to retain said handle portion withinthe confines of either of said circular ends,

19. The combination set forth in claim 13, wherein said restrictingmeans comprises pairs of diametrically opposite tabs projectingoutwardly from said body and engageable with the inner surface of saidbody portion wall adjacent said contoured slot, and said resilient meanscomprises a pair of diametrically opposite projections outstanding fromsaidbody between said tabs and the undersideof said handle portion headand engageable with said edge surfaces of said contoured slot to retainsaidbolt shank in longitudinally adjusted position within said endflange hole. 1 Y i 20. A supporting structure comprising in combination,at least a pair of end frames each having two uprights, tubular beamsinterconnecting said end frames,

each upright having a plurality of slanted keyholeslots along an outwardface thereof, each beam having its open end closed by an angleplateadapted to embrace the upright, one flange'of said plate carrying headedlugs engageable in said slanted keyhole slots tosupport the beam, saiduprights having a plurality of vertically spaced holes along the face,thereof directed toward said beam, the other flange of said plate onsaid beam havinga hole therein alignable with one of the holes in 7 saidhandle portion to restrict the latter for sliding said upright when saidbeam is supported thereby, a load lockfor preventing removal of saidbeam from said upright havingan L-shaped boltrwith a shank aligned withand slidable through the aligned holes in said upright and said beamplate, a handle portion integral with said shank. at right anglesthereto. and having an enlarged head on the free end thereofandexten'ding through a contoured movement-limiting slot in an exteriorwall of said beam, said head engaging an exterior surface of said beamadjacent to said slot, means on movement in said slot, and resilientmeans on said handleportion slidably'engaging the edge surfaces of saidcontoured slot to retain said bolt in adjusted position.

21. The combination set forth in claim 20, wherein said restrictingmeans and said resilient means are incorporated in one unit having agenerally cylindrical body encircling said handle portion. 1

22. The combinationset forth in claim 21, including means on saidcylindrical body embracing the bend in said bolt between said shank andsaid handle portion to resist turning movement of said body on saidhandle portion. g j j I I 23. The combination set forth in claim 21,wherein said restricting means comprises pairs of diametrically oppositetabs projecting outwardly from said body and engageable with the innersurface of said beam wall adjacent said contoured slot.

24. The combination set forth in claim 23, wherein said tabs projectoutwardly from said body and face in spaced relationship the undersideof said handle portion head so as to accommodate therebetween said beamwall adjacent said contoured slot.

25. The combination set forth in claim 21,.wherein said resilient meanscomprises a pair of diametrically opposite projections outstanding fromsaidv body and j said restricting means comprises pairs of diametricallyopposite tabs projecting outwardly from said body and engageable withthe inner surface of said beam wall ad jacent said contoured slot, andsaid resilient means comprises a pair of diametrically oppositeprojections outstanding from said body between said tabs and theunderside of said head and engageable with said edge surfaces of saidcontoured slot to retain said bolt shank in longitudinally adjustedposition.

1. A load lock for use in a pallet rack for locking a beam end to an upright in a frame, comprising in combination an L-shaped bolt and a beam, said bolt having a shank aligned with and slidable through a hole in the end of the beam and adapted to slide through an aligned hole in the frame upright, a handle portion integral with said shank at right angles thereto and having an enlarged head on the free end thereof and extending through a contoured movement-limiting slot in a wall of the beam, said head engaging an exterior surface of said beam adjacent to said slot, a retainer including a generally cylindrical body encircling said handle portion to restrict the latter for sliding movement in said slot, resilient means on said cylindrical body slidably engaging the edge surfaces of said slot to retain said bolt in an adjusted position, and means on said handle portion positively positioning and holding said retainer on said handle portion between said head and said positioning means.
 2. The combination set forth in claim 1, wherein said positioning means is disposed adjacent to the juncture between said handle portion and said shank.
 3. The combination set forth in claim 1, including means on said cylindrical body embracing the bend in said bolt between said shank and said handle portion to resist turning movement of said body on said handle portion.
 4. The combination set forth in claim 1, wherein said retainer includes pairs of diametrically opposite tabs projecting outwardly from said body and engageable with the inner surface of the beam wall adjacent said contoured slot.
 5. The combination set forth in claim 4, wherein said tabs project outwardly from said body and face in spaced relationship the underside of said handle portion head so as to accommodate therebetween the beam wall adjacent said contoured slot.
 6. The combination set forth in claim 1, wherein said resilient means comprises a pair of diametrically opposite projections outstanding from said body and engageable with the edge surfaces of said contoured slot to retain said bolt shank in longitudinally adjusted position.
 7. The combination set forth in claim 6, wherein said contoured slot edge surfaces have a pair of partly circular ends interconnected by a straight section, and have inward projections at the termini of said straight section to retain said handle portion within the confines of either of said circular ends.
 8. The combination set forth in claim 1, wherein said retainer includes pairs of diametrically opposite tabs projecting outwardly from said body and engageable with the inner surface of the beam wall adjacent said contoured slot, and said resilient means comprises a pair of diametrically opposite projections outstanding from said body between said tabs and the underside of said head and engageable with the edge surfaces of said contoured slot to retain said bolt shank in longitudinally adjusted position.
 9. The combination set forth in claim 1, wherein said contoured slot edge surfaces have a pair of partly circular ends, that end nearest the beam end being bounded by a pair of inward projections, the other end being connected to a pair of straight surface portions spaced apart the diameter of said other end, said straight portions having their termini remote from said other end connected to a second pair of inward projections, and straight sections interconnecting said pairs of inward projections, the distance between said partly circular ends being such that when said handle portion is in said other circular end said shank is withdrawn from the hole in the beam end and said bolt may be rotated to remove said restricting means from engagement with the inner surface of the beam wall so that the load lock may be removed from the beam.
 10. The combination set forth in claim 9, including removable means for limiting movement of said handle portion into said other circular end so as to retain said shank in the hole in the beam end.
 11. The combination set forth in claim 10, wherein said removable means comprises a stop member overlying a portion of said other circular end and a bolt to hold said stop member in movemeNt limiting position so that said shank may not be slid from the hole in the beam end.
 12. A beam for use in a supporting structure comprising in combination, an elongated tubuler body portion secured at one end to an end flange, a hole in said end flange opening into the interior of said body portion, a load lock having an L-shaped bolt with a shank aligned with and slidable through said end flange hole, a contoured movement limiting slot in an exterior wall of said body portion, a handle portion integral with said shank at right angles thereto and having an enlarged head on the free end thereof and extending through said contoured slot, said head engaging an exterior surface of said beam adjacent to said slot, means on said handle portion to restrict the latter for sliding movement in said contoured slot, and resilient means on said handle portion slidably engaging the edge surfaces of said contoured slot to retain said shank in an adjusted position in said end flange hole.
 13. The combination set forth in claim 12, wherein said restricting means and said resilient means are incorporated in one unit having a generally cylindrical body encircling said handle portion.
 14. The combination set forth in claim 13, including means on said cylindrical body embracing the bend in said bolt between said shank and said handle portion to resist turning movement of said body on said handle portion.
 15. The combination set forth in claim 13, wherein said restricting means comprises pairs of diametrically opposite tabs projecting outwardly from said body and engageable with the inner surface of said beam body portion wall adjacent said contoured slot.
 16. The combination set forth in claim 15, wherein said tabs project outwardly from said body and face in spaced relationship the underside of said handle portion head so as to accommodate therebetween said beam wall adjacent said contoured slot.
 17. The combination set forth in claim 13, wherein said resilient means comprise a pair of diametrically opposite projections outstanding from said body and engageable with said edge surfaces of said contoured slot to retain said bolt shank in longitudinally adjusted position within said end flange hole.
 18. The combination set forth in claim 17, wherein said contoured slot edge surfaces have a pair of partly circular ends interconnected by a straingt section, and have inward projections at the termini of said straight section to retain said handle portion within the confines of either of said circular ends.
 19. The combination set forth in claim 13, wherein said restricting means comprises pairs of diametrically opposite tabs projecting outwardly from said body and engageable with the inner surface of said body portion wall adjacent said contoured slot, and said resilient means comprises a pair of diametrically opposite projections outstanding from said body between said tabs and the underside of said handle portion head and engageable with said edge surfaces of said contoured slot to retain said bolt shank in longitudinally adjusted position within said end flange hole.
 20. A supporting structure comprising in combination, at least a pair of end frames each having two uprights, tubular beams interconnecting said end frames, each upright having a plurality of slanted keyhole slots along an outward face thereof, each beam having its open end closed by an angle plate adapted to embrace the upright, one flange of said plate carrying headed lugs engageable in said slanted keyhole slots to support the beam, said uprights having a plurality of vertically spaced holes along the face thereof directed toward said beam, the other flange of said plate on said beam having a hole therein alignable with one of the holes in said upright when said beam is supported thereby, a load lock for preventing removal of said beam from said upright having an L-shaped bolt with a shank aligned with and slidable through the aligned holes in said upright and said beam plate, a handle portion integraL with said shank at right angles thereto and having an enlarged head on the free end thereof and extending through a contoured movement-limiting slot in an exterior wall of said beam, said head engaging an exterior surface of said beam adjacent to said slot, means on said handle portion to restrict the latter for sliding movement in said slot, and resilient means on said handle portion slidably engaging the edge surfaces of said contoured slot to retain said bolt in adjusted position.
 21. The combination set forth in claim 20, wherein said restricting means and said resilient means are incorporated in one unit having a generally cylindrical body encircling said handle portion.
 22. The combination set forth in claim 21, including means on said cylindrical body embracing the bend in said bolt between said shank and said handle portion to resist turning movement of said body on said handle portion.
 23. The combination set forth in claim 21, wherein said restricting means comprises pairs of diametrically opposite tabs projecting outwardly from said body and engageable with the inner surface of said beam wall adjacent said contoured slot.
 24. The combination set forth in claim 23, wherein said tabs project outwardly from said body and face in spaced relationship the underside of said handle portion head so as to accommodate therebetween said beam wall adjacent said contoured slot.
 25. The combination set forth in claim 21, wherein said resilient means comprises a pair of diametrically opposite projections outstanding from said body and engageable with said edge surfaces of said contoured slot to retain said bolt shank in longitudinally adjusted position.
 26. The combination set forth in claim 25, wherein said contoured slot edge surfaces have a pair of partly circular ends interconnected by a straight section, and have inward projections at the termini of said straight section to retain said handle portion within the confines of either of said circular ends.
 27. The combination set forth in claim 21, wherein said restricting means comprises pairs of diametrically opposite tabs projecting outwardly from said body and engageable with the inner surface of said beam wall adjacent said contoured slot, and said resilient means comprises a pair of diametrically opposite projections outstanding from said body between said tabs and the underside of said head and engageable with said edge surfaces of said contoured slot to retain said bolt shank in longitudinally adjusted position. 